Mix pork, finely chopped shrimp, filling ginger, filling soy sauce and sesame oil until evenly combined. Divide mentally into 24 portions, about 2 level teaspoons each.
Place a portion in the center of a wrapper, moisten two adjacent edges with the measured sealing water and fold into a triangle, pressing out air. Moisten one lower corner and join the two lower corners, then repeat with all wrappers, keeping unused wrappers covered.
Bring broth, broth ginger and broth soy sauce to a gentle boil in a 5-quart pot. Lower the wontons into the broth one at a time, then reduce to a steady gentle simmer.
Simmer for 6 to 8 minutes, stirring gently once to prevent sticking, until wrappers are tender and the center of the largest wonton reaches 160°F with fully opaque shrimp.
Add bok choy for the final 2 minutes of cooking. Divide 6 wontons and broth among each of 4 bowls and add the measured scallions evenly.